Overcharge and rude treatment

Good day My daughter’s is with Dr PJ Stapelberg in Nelspruit( Orthodontist). Last year May we paid for a Hawley device. The device broke a second time this week. We went to Dr Stapelberg and the device was send to Expodent laboratory . I was shocked when I received the Statement from Dr Stapelsberg. They charged me R1008. 90. I phoned them to query that and the lady at accounts said she can’t do anything about it and I should have said that this was the second time it breaks, that that is the amount and we must pay it. I asked her what is the R520 repair cost for if the labs cost is R385.90 and she said it’s the Dr’s cost for their own work in the back. I asked what work and she couldn’t answer. I also asked why must I pay R65 infection control twice because it was on the statement and on the email she sent me she add another R65. I also asked what is it for because my daughter said sometimes Dr doesn’t even put gloves on. I phoned the lab and they confirm that their cost is only R358.90. The practice phoned me within 10 min after the accounts lady said the Dr’s left for home already. Dr Stapelbergs wife who is also a Dr start shouting at me because this is the second time I query an account with them. The previous time was a year ago, and I had a problem (actually a lot of people in Nelspruit do) about the way they treat patients, and no one dare to query anything because then Dr Stapelsberg wife phone you or email you and give you a mouth full. Everyone is worried about how they will treat your child in future so you just hold your tongue and pay. But this time I insisted that I want to know what is the R520 repair cost for on the statement if the lab did the repairs. She, Dr Stapelberg just shouted at me and said I don’t have any right to claim how the amount was made up or for what’s it for because it’s their right to charge what the medical aid codes is or something like that. I told her that the new device cost me R1403 last year May and now I must pay R1008 for a repair and that doesn’t make any sense . She just said she don’t care and if I don’t pay they will hand me over and I better not sit foot in their practice ever again.